Abstract: This invention is a method and apparatus for detecting the presence of gaseous oxygen and measuring the amount present. In the practice of the invention, luminescence from a luminophor compound is quenched by oxygen. The luminiphor is a conjugated aromatic carbonyl. The intensity of the emitted light is related to the concentration of oxygen in the atmosphere surrounding the conjugated aromatic carbonyl compound. The luminophor compound is located on a polar substrate having free hydroxyl groups at its surface and also having at its surface, in locations adjacent to the luminophor compound, a halogenated hydrocarbon compound containing at least one halogen selected from a group consisting of chlorine, bromine, and iodine. In a preferred embodiment, the invention comprises an oxygen sensor utilizing a fiber-optic light guide to conduct excitation light to a substrate comprised of activated silica gel particles having methylene chloride and N-methylacridone co-deposited on them.

Abstract: In order to simplify the operation for determination of the acid-base status of blood, composed of the values for pH, pCO.sub.2 and the base excess BE, the base excess BE is determined through measurement of the pH-value at a pCO.sub.2 of about 0 mn Hg. The pH-values may be determined photometrically, in which case the indicator solution for measuring the actual blood-pH is an aqueous solution of 40 micromol/l bromthymol blue plus 0.2 g/l sodium dodecylsulfate plus 1% ethanol; and for measurement of the base excess BE is an aqueous solution of 65 micro mol/l naphtholphthalein plus 0.2 g/l sodium dodecylsulfate plus 15% dimethylsulfoxide, which are measured at a wavelength of 635 nm. If desired, one may use a single solution for measuring both actual blood-pH as well as the base excess BE, composed of 16 micromol/l bromthymol blue plus 34 micromol/l naphtholphthalein plus 0.15 g/l sodium dodecylsulfate, which is measured at 615 nm wavelength.

Abstract: Disclosed is a method for determining the degree of freshness of such raw, frozen and processed perishable foodstuffs as meat, poultry and fish and an instrument therefor. The degree of freshness can be easily determined by the method of the present invention in shorter periods of time than by the conventional methods.The method of this invention comprises determining the amount of certain decomposition products of adenosine triphosphate such as hypoxanthine, inosine and inosinic acid by measuring the consumption of dissolved oxygen while each compound is subjected to action by certain enzymes, i.e., hypoxanthine by xanthine oxidase, inosine by nucleoside phosphorylase and inosinic acid by alkaline phosphatase, nucleoside phosphorylase and xanthine oxidase.

Abstract: An apparatus for sensing the concentration of a component such as oxygen in a medium such as blood. The apparatus includes an elongated signal transmitter and a sensing element at one end thereof. A substantially rigid sleeve is secured around such end to provide a pocket for the sensing element.

Abstract: A colorimetric test tube having a colorimetric indication which includes a simple detection system for testing gases dissolved in liquids. The test tube has an indicator for the colorimetric indication of gaseous substances to be detected and it has an opening covered against the environment to be tested with a hydrophobic membrane which is permeable to the substances whose presence is to be detected and which can be used for indicating the presence of gases dissolved in liquids. The membrane is advantageously sealed with a covering which dissolves upon immersion of the test tube in a liquid.

Abstract: Correcting an initial measurement of the concentration of a first water soluble species dissolved in a water-based component of a biological fluid that also includes a second water soluble species and a volume occupying component, the initial measurement having been taken using an original sample of the fluid that had been diluted by an amount of additional aqueous solution to form a diluted sample is disclosed; the concentration of the second water soluble species is measured in an undiluted sample of the biological fluid to obtain a direct concentration and is measured using a diluted sample of the fluid to obtain an indirect concentration, and the initial measurement of concentration of the first species is adjusted based on a combination of the direct and indirect concentration determinations of the second species.

Abstract: An electrochemical method for determining the total carbonate content of fluids, especially biological fluids. According to the invention, using an ion-selective electrode, the concentration of certain ions dissociable from carbon acid or affecting the dissociation balance is first measured for the fluid. The fluid is then mixed with another fluid containing a reactive component that changes the ionic concentration just measured, whereupon the concentration is again measured by means of an ion-selective electrode, thus producing two different measurement results, from which the total carbonate content can be determined. The measurement preferably relates to the pH of the fluid, while metallic ions such as Cu.sup.2+, forming a complex with hydrocarbonate ions, are used as the component to be added to alter the pH.

Abstract: A composition of matter useful for sensing the concentration of an ionic component in a medium comprising a cationic or anionic matrix material and a sensing component chemically bonded to the matrix material and being effective to provide a signal in response to the presence of the ionic component in the medium.

Abstract: A method for titration flow injection analysis by introducing a multicomponent sample into a carrier stream which flows into a mixing/sensing cell and titrating with a reactant more than one component of the sample by sensing a plurality of endpoints. The apparatus of the invention includes a stirring means within the mixing/sensing cell which generates helical flow within the cell so that bubbles are not retained in the cell.

Abstract: There is disclosed herein an automated sample preparation system for chemical assay of samples of materials. The sample preparation system includes a sample preparation chamber which includes a removable cup for taking to the location of solid or very viscous samples. The cup may be attached in sealing relationship to a cap through which extends various utilities such as a mixer/grinder to grind solid samples and mix non-homogeneous samples, a fill pipe to pump in liquid samples, an effluent pipe in the sump of the cup to allow pump of samples and solvents and a nozzle to allow liquids to be sprayed against the walls. A sample metering valve associated with the sample preparation chamber allows a known volume of sample to be isolated so that solvent may be pumped in to dilute the sample to a user defined concentration.

Abstract: An apparatus for measuring the concentration of a component in a medium comprising:an optical sensor including at least one optical indicator for providing an optical signal which varies in response to the presence of a component in a medium;an optical signal fiber capable of transmitting the optical signal from the optical sensor; anda supply reservoir associated with the optical sensor and acting to provide additional optical indicator to the optical sensor.

Abstract: A system for expression of coding sequences for desired heterologous proteins in procaryotic hosts whereby the protein is produced intracellularly in soluble, biologically active form, is disclosed. The expression is obtained by ligation of the coding sequence downstream of, and proximally to, but out of reading frame with, the terminated leader encoding sequence for a secreted bacterial protein, such as alkaline phosphatase. The resultant proteins are influenced by the leader sequence codons to effect the desired three-dimensional conformation, but not to effect secretion.

Abstract: A sensor comprising a sensing element capable of sensing a component in an aqueous medium and an overcoating at least partially covering the sensing element. The overcoating comprises a water insoluble, component permeable, cross-linked cellulosic material and an effective amount of an opaque agent.

Abstract: Perfluorocarbon emulsion formulations are oxygenated prior to use by means of a portable oxygenation system. The blood substitute is in a closed container or bag. An oxygen-containing gas is introduced into the bag from a separate container. The bag is continuously agitated for a sufficient time to increase the pO.sub.2 of the perfluorocarbon emulsion formulations to a desired pressure, e.g., to at least 600 mmHg. In one embodiment, the system used for oxygenation of the perfluorocarbon emulsion formulations comprises a small tank for gas having an inlet port and an outlet port fitted with shut-off valves. The outlet port is adapted to be connected to a filter which, in turn, is adapted to be connected to the inlet port of a three-way valve. The primary outlet of the three-way valve is adapted to mount a hypodermic needle which is adapted to be pushed through a rubber septum in a port of the bag to communicate with the interior of the bag.

Abstract: A method for establishing a treatment protocol for correcting an abnormal condition of disease in a living organism is described. The method comprises the steps of analyzing body fluids from normal and abnormal individuals to generate analysis patterns of the normal and abnormal fluids, comparing the patterns to determine differences in the patterns, and establishing a treatment protocol for the abnormal individual through chemical or metabolic therapy which treating will normalize the abnormal pattern.

Abstract: A sensor for determining the partial pressure of carbon dioxide in a liquid, which comprises a carbon dioxide - permeable, liquid and ion-impermeable membrane enveloping an aqueous medium containing an absorber, a fluorescer and a source of bicarbonate ions, which medium exhibits variations in pH as a function of the partial pressure of dissolved carbon dioxide, the ratio of absorber to fluorescer and the characteristics of the absorption spectrum of the absorber and the excitation and emission spectra of the fluorescer being such that the partial pressure of carbon dioxide in the liquid may be determined from the pH of the aqueous medium as measured by the intensity of the fluorescent emission of the fluorescer.

Abstract: A method and an apparatus are described for determining the partial pressures of gases in blood, in which a membrane filter is used to separate plasma which passes to a blood gas analyzer.

Abstract: The application relates to a method and apparatus for testing the concentration of a selected atomic scale species in a thick liquid, such as blood. The blood flows through a chamber that is in part defined by a microporous dialysis membrane permeable to atomic scale species. A measuring cell including a second chamber filled with a clean liquid is defined by the other plane of the membrane. The measuring cell incorporates a sensor having an electrode coated with a material permeable only to a selected ionic species.

Abstract: A measuring canal is provided which is connected to a catheter. The canal includes a measuring sensor and a reference sensor. The catheter includes several lumens that have a common opening to the liquid measuring medium. The flow direction of an infusion solution at the opening is reversible. A second lumen of the catheter is connected to the measuring canal which is provided with at least one measuring sensor and with at least one reference sensor as well as with a device for setting the outflow of the apparatus to a predetermined velocity. The flow of an infusion fluid and the liquid medium alternates in such a fashion that during a first time interval the measuring sensor is coupled to the liquid medium and the reference sensor is coupled to the infusion solution. In a second interval the situation is reversed so that the original measuring sensor is coupled to the infusion solution and the original reference sensor is connected to the liquid medium.

Abstract: A method of measuring the concentration of carbon dioxide in a medium by determining the water content in a pH-independent sensor system comprising an optical fiber having attached thereto a fluorescence indicator embedded in a carrier matrix containing a miscible mixture of water and non-aqueous solvent in predetermined proportions and being separated from said medium by a gas-permeable, water-impermeable diffusion membrane, said indicator, when excited by excitation radiation of a predetermined wavelength, emitting fluorescent emission whose intensity is dependent upon the ratio of water to non-aqueous solvent present in the system such that the ratio of intensities of emitted radiation is therefore proportional to the amount of water present and diffusion of carbon dioxide through said gas-permeable membrane and subsequent reaction with water to deplete the water content of the system induces a change in the intensities of said emissions, which method comprises transmitting excitation radiation through sai

Abstract: A gas sensor has a first aqueous phase. The aqueous phase is composed of a soluble dye in a buffer. One or more additional agent can be further added to the aqueous phase as for instance an emulisification enhancement agent. The aqueous phase is homogenized into a polymeric precursor forming a emulsion of the aqueous phase in the polymeric precursor. A catalyst and a cross-linking agent are added and the polymeric precursor material allowed to polymerize to form an emulsoid of micro-compartments of the aqueous phase in a polymeric second phase. The micro-compartments of the aqueous phase are dispersed through and permanently suspended in the polymeric second phase.

Abstract: Partition membranes which are permeable to blood electrolytes fabricated from crosslinked polyetherurethane compositions having from 20 to 50% hard segments. The membranes absorb from 50 to 120% of their dry weight of water and have electrolyte diffusion constants of up to 1.times.10.sup.-6 cm.sup.2 /sec. The membranes are included in electrochemical, fiber optic and solid state blood electrolyte sensors to provide blood compatible surfaces and to ensure that blood components deleterious to analysis of electrolyte in the blood remain separated from the sensing elements.

Abstract: A continuous on-line monitor of carbon dioxide dissolved in high purity water includes a cation conductivity cell and associated bridge for measuring first and second cation conductivities at first and second temperature and a heater for heating the sample from the first to the second temperature. A microcomputer calculates first and second concentrations of a fully dissociated acid alone and carbon dioxide alone, respectively, which will produce the first measured cation conductivity at the first temperature and then determines the actual carbon dioxide concentration from the first and second concentrations and the second measured cation conductivity.

Abstract: A clinical chemistry analyzer system for blood chemistry analysis is disclosed. Two major parts comprise the system. One part is a discardable sensor cartridge which contains a bank of sensors, calibration fluid containers, conduit means and an external peristallically pumpable tube section. The other part is an analysis machine which interfaces with the discardable cartridge and has means to drive the peristaltic pump as well as means to interface with the sensors of the cartridge to provide a readout therefrom. The system is adapted to be made part of a heart/lung machine sustaining a patient in order to sample and monitor the venous and arterial blood flow thereof.

Abstract: An apparatus for sensing characteristics of a substance, such as blood, including a membrane support having first and second recesses and first and second dissimilar membranes extending over the first and second recesses, respectively. The membrane support has a groove between the recesses, and edge portions of the membranes extend into the groove on the side thereof adjacent the first recess. A retaining bar is received within the groove, and the membranes are tightly held between the retaining bar and the wall of the groove to form a smooth, essentially continuous surface. The membrane support forms a portion of a flow passage so that blood can flow along the membranes. First and second sensors are mounted on the sides of the first and second membranes opposite the flow passage for sensing characteristics of the blood. The first and second sensors engage the first and second membranes, respectively, to tension the membranes.

Abstract: A luminescent layer for use in apparatus for determining the oxygen concentration in gases, fluids and tissues by measuring the decrease in the light emission of a luminescent surface irradiated with an excitation light of a certain wavelength, where the luminescent dye forms a homogeneous mixture with the light-transparent layer substance, in which case the surface may also have a fine-grained structure.

Abstract: A method of neutralizing the electrostatic forces in liquids or solutions in liquid phase, preferably blood and blood solutions, respectively. The electrostatic forces primarily consist of surface tension and interrepellant forces between particles in the solution.The purpose of the invention is obtained by adding polypropylene glycol H[OCH(CH.sub.3)CH.sub.2 ].sub.n OH to the liquid or solution. Polypropylene glycol possesses properties allowing it to neutralize the electrostatic forces without affecting the red blood cells.

Abstract: Very stable, polymer-based electrochemical devices, formed by polymerization of thiophene or a derivative such as 3-methylthiophene which is durable in an aqueous electrolyte over a wide pH range, which respond rapidly to chemical or electrical signals, are disclosed. In one embodiment, the device functions as an extremely sensitive sensor which measures changes in chemical concentration or pH. For example, a poly-3-methylthiophene-based device is sensitive to as little as 8.times.10.sup.-16 moles of an oxidant which reversibly interacts with the polymer, including gas phase oxidants such as I.sub.2. In a variation of the polymer-based device, a catalyst such as a noble metal or an enzyme, is dispersed on or within the conducting polymer matrix so that the device is responsive to chemicals such as H.sub.2 and O.sub.2 which the polymer would otherwise respond very slowly to.

Abstract: Method and apparatus are provided to equilibrate a solution contained in a conventional syringe. The syringe is positioned so that the tapered end of the syringe is upward relative to the flanged end of the syringe. An equilibration tube member is inserted into the tapered end of the syringe. Equilibrating gas of a known composition is delivered to an input cavity formed in a heat block. The equilibrating gas is humidified in a humidifying chamber after it exits the input cavity. The humidified, equilibrating gas then passes into an output cavity formed in the heat block. The equilibration tube member receives the gas from the output cavity and carries it downwardly into the syringe where it exits the equilibration tube member into the equilibration solution. The equilibrating gas passes upwardly through the solution to produce an equilibrated sample. Gas passing from the solution is able to exit the syringe through its tapered end.

Abstract: An apparatus for sensing characteristics of a substance, such as blood, including a membrane support having first and second recesses and first and second dissimilar membranes extending over the first and second recesses, respectively. The membrane support has a groove between the recesses, and edge portions of the membranes extend into the groove on the side thereof adjacent the first recess. A retaining bar is received within the groove, and the membranes are tightly held between the retaining bar and the wall of the groove to form a smooth, essentially continuous surface. The membrane support forms a portion of a flow passage so that blood can flow along the membranes. First and second sensors are mounted on the sides of the first and second membranes opposite the flow passage for sensing characteristics of the blood. The first and second sensors engage the first and second membranes, respectively, to tension the membranes.

Abstract: Cell useful for equilibrating a hydrophilic liquid such as an aqueous solution held therewithin with a gas composition. The cell comprises a tube having an open end and a closed end, the closed end comprising a porous member having a hydrophobic surface, the member being impervious to flow of a hydrophilic liquid therethrough when the tube is filled therewith and positioned vertically with a closed end thereof downwardly and being permeable to pressurized flow of the gas composition upwardly therethrough. The invention is also concerned with such a cell in an apparatus for equilibrating a hydrophilic liquid such as an aqueous solution with a gas composition, which apparatus comprises a gas vessel having therewithin a gas of a selectable composition at a pressure above ambient atmospheric pressure, flow control means for receiving flow from said vessel and controlling a flow rate therefrom and conduit means leading from the flow control means to a solution cell having therewithin a hydrophilic liquid.

Abstract: The invention is concerned with apparatus for equilibrating an aqueous solution with gas. The apparatus includes a gas vessel having therewithin a gas of a selectable composition at a pressure above ambient atmospheric pressure. Flow control means receive flow from the vessel and control a flow rate therefrom. A solution tube is provided having an aqueous solution therewithin. Conduit means lead from the flow control means to the tube below a liquid level of the aqueous solution. Means are also provided for causing the gas to be delivered within the aqueous solution below the liquid level as a plurality of bubbles. The process of the present invention is directed at simultaneously equilibrating a plurality of aqueous solutions each with one of a plurality of gas compositions.

Abstract: Methods and devices for assaying the sensitivity of of biopsied cells to therapeutic agents are disclosed. Cells are cultured in artificial organs and then contacted with a fluorogenic substrate such that living cells accumulate a characteristic amount of fluorescence. The agent is then introduced into the organ and changes in the fluorescence released by the cells serve as an indicator of the sensitivity of the cells to the agent.

Abstract: Method and apparatus for the batch preparation of sample aliquots by solvent extraction and separation of soluble species from sample comprising nonsoluble particulate, which comprises a receptacle which defines a sample receiving space into which a measured amount of sample is placed, a fluid-permeable filter which is remote from and communicates with the sample receiving space, means to add a metered quantity of solvent to the sample receiving space, means to supply pressurized gas to the sample receiving space to slurry the solvent with the sample, means to invert the receptacle to position the slurry into filtering contact with the filter, and means to collect a sample aliquot comprising the filtered liquid phase of the slurry.

Abstract: A method and apparatus for measuring of concentrations of components of a fluid mixture. One side of a membrane permeable to the component to be determined is contacted with a sample of the fluid mixture to be analyzed. The second side of the membrane is contacted with a test fluid passing the membrane at different speeds. The resultant properties of the test fluid are determined for the different speeds of flow past the membrane and the measured values allow to determine the concentration or partial pressure of the component in the fluid mixture. The fluid mixture is preferably blood and the components can be oxygen and carbon dioxide. Preferably the membrane provides a spiral path for the test fluid in order to allow employing a more rapid flow of the test fluid past the membrane. Furthermore, such a configuration can be combined with a catheter for hemodynamic blood pressure measurement thereby providing a single probe for continuous monitoring of blood in clinical practice.

Abstract: For plotting an equilibrium curve representative of the relation between the oxygen saturation value of a hemoglobin sample, such as blood, and a changing oxygen partial pressure level in a gas, the sample is initially oxygenated by an oxygen-containing gas till it is completely saturated with oxygen, and thereafter by a controlled supply of deoxygenating gas to the volume of gas acting on the sample the oxygen partial pressure is decreased in a controlled manner. The oxygen saturation value is determined from the photometrically measured light absorption parameter of the sample in the measuring space.

Abstract: In order to simplify the operation for determination of the acid-base status of blood, composed of the values for pH, pCO.sub.2 and the base excess BE, the base excess BE is determined through measurement of the pH-value at a pCO.sub.2 of about 0 mm Hg. The pH-values may be determined photometrically, in which case the indicator solution for measuring the actual blood-pH is an aqueous solution of 40 micromol/l bromthymol blue plus 0.2 g/l sodium dodecylsulfate plus 1% ethanol; and for measurement of the base excess BE is an aqueous solution of 65 micro mol/l naphtholphthalein plus 0.2 g/l sodium dodecylsulfate plus 15% dimethylsulfoxide, which are measured at a wavelength of 635 nm. If desired, one may use a single solution for measuring both actual blood-pH as well as the base excess BE, composed of 16 micromol/l bromthymol blue plus 34 micromol/l naphtholphthalein plus 0.15 g/l sodium dodecylsulfate, which is measured at 615 nm wavelength.

Abstract: An analysis system for measuring a plurality of parameters of a fluid sample comprises a housing, and a flow-through cell in the housing that has opposed surfaces with at least two ports in each surface. One of the ports is an inlet port, a second of the ports is an outlet port, and at least two of the ports are sensing ports. A sample flow path including a serpentine portion in the cell serially connects the ports and extends from a port in one surface to a port in the other surface and back to a port in the one surface, and a sensor is disposed in sealing engagement with each sensing port and forms a portion of the serpentine flow path so that sample fluid to be analyzed contacts a surface of each sensor.

Abstract: Method and apparatus for determining the gaseous content of a diluent, such as determining the oxygen or carbon dioxide content of blood. A sample of the diluent whose gaseous content is to be measured is anaerobically pumped past a junction tee after being placed in a reservoir. A second diluent, not part of the sample, is equilibrated with a gas (not the gas to be measured) in a first tonometer. This second equilibrated diluent is pumped past the junction tee where it is mixed with the diluent sample. The gas in the second diluent is selectively chosen to drive the gas to be measured into the dissolved phase. The diluent mixture is then allowed to flow through an appropriate sensor that senses the presence of the gas to be measured. This first measurement is stored in a suitable controller, such as a microprocessor.

Abstract: An apparatus for analyzing biological liquids comprises a measuring block including measuring means for measuring characteristics of said liquids. The measuring block is mounted within a thermal shield or housing by means of a base member interconnecting a minor part of the inner wall of the housing and the measuring block so as to define a space between the inner walls of the housing and the measuring block, said space being filled with air or another medium having a poor thermal conductivity.The thermal shield or housing and the base member are made of a material with good thermal conductivity, and heating and/or cooling means are arranged in heat conductive contact with the said shield. The function of the heating and/or cooling means is controlled by a temperature sensor arranged in heat conductive contact with the measuring block, so as to maintain the temperature of said block at a substantially constant predetermined value.

Abstract: A method and system for measuring the oxygen carrying capacity of normal and abnormal hemoglobins and red cells under controlled pH, ionic strength, temperature and gas conditions is described. A blood sample and a physiologically balanced medium are placed in a cuvette and means are associated therewith for measuring the fractional saturation of the sample and the partial pressure of the oxygen (sometimes referred to as the oxygen tension) and provide output signals to an X-Y plotter for continuous recording. Preferably, means for maintaining the temperature of the medium and the blood sample is provided.

Abstract: A test apparatus for measuring blood characteristics comprises a measuring head having a measuring electrode and a reference electrode arranged in spaced relationship and a closure membrane covering a portion of said head, and an attachment connectable to said head having a wall defining a support membrane which is engageable on the closure membrane. The attachment defines a chamber for the blood sample in which the support membrane forms a bottom wall thereof so that the membrane supporting the blood is in contact with the closure member and thus is capable of being heated by a heater contained in the head without coming into contact with or contaminating the blood sample. The attachment while permitting the measurement to be made does not allow the blood being tested to come into contact with the measuring head. The attachment may be either disposed of or cleaned for re-use.